AB1260 SIGNIFICANCE OF WHOLE-BODY MRI IN CHILDREN WITH RHEUMATIC DISEASES
Authors: I. Nikishina, Z. Kolkhidova, L. Blank, T. Pachkoria, S. Arsenyeva, V. Matkava, A. Shapovalenko, M. Shalygina
Journal: Annals of the Rheumatic Diseases (2022)

Background Whole-body MRI (WB-MRI) has the potential to detect early or hidden signs of inflammation and seems to be more informative test than X-ray and ultrasound methods for bone and joints diseases. WB-MRI is important for identification of asymptomatic inflammation areas that are not available for clinical examination methods (sacroiliitis, TMJ). WB-MRI can become a tool for monitoring the progression of the disease and the efficacy of therapy. There is not enough data of knowledge about the role of WB-MRI in children with JIA. Objectives To evaluate the results of WB-MRI in children with rheumatic diseases (RD) in a single-center retrospective study. Methods 57 WB-MRI studies performed in children with RD in our center as a part of real-life diagnostic procedures. Results Among 57 children there are 22 boys and 35 girls, the average age is 13 years [11; 16]. 33 patients were examined once, 20 children twice after the initial course of therapy, two children underwent WB-MRI three times to evaluate the dynamics. It was most important to detect inflammatory lesions in multifocal non-bacterial osteomyelitis (mf-NBO). The structure of diagnosis and therapy before and after WB-MRI is present in Table 1. Table 1. The effect of MRI on changes in the structure of diagnoses and approaches to therapy Before WB-MRI After WB-MRI Diagnosis: Juvenile idiopathic arthritis (JIA) 22 12 JIA+ mf-NBO 22 30 JIA+ mf-NBO +Psoriasis 5 8 JIA+ mf-NBO +FMF 1 1 JIA+ Psoriasis 2 0 JIA+IBD 1 1 (JIA+IBD+ mf-NBO) Fibrodisplasia ossificans progressive (FOP) +JIA 1 1 Systemic JIA 1 1 Juvenile dermatomyositis (JDM) 1 1 Systemic lupus erythematosus (SLE) 1 1 SLE+ mf-NBO 0 1 Therapy: NSAIDs mono 17 12 DMARDs 26 29 Biologics: / bDMARDs: anti-TNFα Tofacitinib Abatacept 121011 272151 Bisphosphonates 4 5 No current therapy 3 0 11 patients have multimorbidity (in addition to RD, one girl has Down syndrome). 5 pts had severe hypermobility syndrome patients making it difficult to identify inflammation due to the discrepancy between objective signs and the absence of limitation of joint mobility. 2 patients had multiple ankylosis. 7 patients underwent surgical interventions: 5 because of vertebral fracture, 2 because of osteomyelitis. The WB-MRI revealed: 48 polyarthritis signs, 33 osteitis, 3 osteonecrosis, 11 sacroiliitis, 1 sequestration, 1 epiphyseolysis, 1 initial signs of myositis. Surgical intervention was recommended to two patients after the diagnosis of WB-MRI (sequestration of the osteomyelitis focus and vertebral fracture). Figure 1. WB-MRI 10-yrs old girl with JIA+ mf-NBO +Psoriasis. Than WB-MRI picture 4 months after the Etanercept administration. Positive dynamics in the sacroiliac joints, but the persistence of osteitis in the right radius, calcaneus, femur with the forming lytic destruction. The principal significance and purpose of the performance of WB-MRI were disease control (continuation of therapy) - 22 (39%), the onset of DMARDs/bDMARDs – 17 (30%), the change of bDMARDs - 2 (3%), differential diagnosis – 16 (28%). Conclusion WB-MRI is useful for detecting asymptomatic and radiologically hidden lesions in JIA. Early diagnosis leading to appropriate treatment can prevent long-term structural damage to the joint. WB-MRI is a important tool for the diagnosis and diseases control in children with RD. Disclosure of Interests None declared